Numerous short and narrow rivers rise in the central highland; the most significant include the Kala, Kalu, Kirindi and Yan rivers.

Off the northwestern coast of Sri Lanka a chain of limestone shoals, known as Adam's Bridge, separates the Gulf of Mannar from the Palk Strait, and runs along the water to the southeastern coast of India.

At one point it was completely passable, but Adam's Bridge broke apart in the late 15th century when a cyclone hit the region. Today, the bridge is 18 miles (30 km) long, and ranges from 3 - 30ft. (1 - 10m) deep in some areas.